Devices such as handheld computers, typically referred to as personal digital assistants (PDAs), are designed to have configurable input and output features. For example, some PDAs have configurable button options. Other PDAs have manual or application specific screen rotations.
PDAs generally have a designated orientation, centered around the use of the input/output features. For example, a typical PDA has a rectangular screen. Visual indices indicate a left and right side of the display. When content such as text is provided on the display, the content has a fixed orientation, with the left-right and top-down directions being fixed on the display. Similarly, the buttons on the PDA usually have a vertical orientation, set just below the display.
Given the fixed orientation of the typical PDA, the user has limits in how the device can be configured and oriented. For example, the device must be picked up and used in the correct orientation in order for the display to be used. The button functions assignments may be configurable, but the buttons have fixed physical locations relative to the display of the PDA.